Process for producing crystals of a diazabicyclooctane derivative

Abstract

A process for producing crystals of a compound represented by the following formula (I):by crystallizing the compound from an aqueous solution containing the compound and an inorganic salt, such as sodium chloride. Such crystals can be subjected to lyophilization to provide a lyophilized composition having a desirable storage stability.

The invention claimed is: 
     
       1. A process for producing crystals of a compound represented by the following formula (I): 
       
         
           
           
               
               
           
         
       
       comprising crystallizing the compound from an aqueous solution containing the compound and an inorganic salt, without previous purification of the compound with a column,
 wherein a crystalline form I of the compound having characteristic peaks appearing at a lattice spacing (d) of 7.34, 5.66, 5.53, 5.30, 5.02, 4.66, 4.37, 4.28, 4.06, 3.68, 3.62, 3.47, 3.36, 3.30, 3.16, 3.11, 3.03, 2.99 and 2.50 Å in a powder X-ray diffraction pattern is produced. 
 
     
     
       2. A process for producing crystals of a compound represented by the following formula (I): 
       
         
           
           
               
               
           
         
       
       comprising crystallizing the compound from an aqueous solution containing the compound and an inorganic salt, without previous purification of the compound with a column,
 wherein the aqueous solution containing the compound and an inorganic salt is obtained by dissolving the compound and the inorganic salt together in water, or by dissolving either of the compound or the inorganic salt in water and then dissolving the other in the resultant solution, and 
 wherein a crystalline form I of the compound having characteristic peaks appearing at a lattice spacing (d) of 7.34, 5.66, 5.53, 5.30, 5.02, 4.66, 4.37, 4.28, 4.06, 3.68, 3.62, 3.47, 3.36, 3.30, 3.16, 3.11, 3.03, 2.99 and 2.50 Å in a powder X-ray diffraction pattern is produced. 
 
     
     
       3. A process for producing crystals of a compound represented by the following formula (I): 
       
         
           
           
               
               
           
         
       
       comprising crystallizing the compound from an aqueous solution containing the compound and an inorganic salt, without previous purification of the compound with a column,
 wherein the compound is crystallized by adding a poor solvent to the aqueous solution containing the compound and the inorganic salt, and 
 wherein a crystalline form I of the compound having characteristic peaks appearing at a lattice spacing (d) of 7.34, 5.66, 5.53, 5.30, 5.02, 4.66, 4.37, 4.28, 4.06, 3.68, 3.62, 3.47, 3.36, 3.30, 3.16, 3.11, 3.03, 2.99 and 2.50 Å in a powder X-ray diffraction pattern is produced. 
 
     
     
       4. The process according to  claim 3 , wherein the poor solvent is an alcohol. 
     
     
       5. The process according to  claim 1 , wherein the compound is crystallized by subjecting the aqueous solution containing the compound and the inorganic salt to lyophilization.